Circular saws, particularly relatively large ones, are used in various applications which include, but are not limited to, felling trees and other natural plant growth in the forestry industry, cutting rock and/or earth in the mining and construction industries, cutting up items such as used tires and other man-made products in various industrial applications, and in agriculture. Relatively smaller circular saws are further used in countless other smaller-scale applications, from home renovation to commercial construction. Depending on the type of circular saw, the central disk of the saw either rotates (for the smaller circular saws) or remains rotationally fixed but has teeth on linked holders which rotate about the periphery of the saw disk, much as per chain saws.
Regardless of the type of circular saw, a plurality of such cutting teeth rotate, whether independently about the periphery of the rotationally-stationary disk or together with the rotating disk when fixed thereto, in order to cut into the workpiece material to be cut.
Particularly with known saw teeth used on large circular saws, such as those used for felling trees or cutting through large volumes of man-made materials, each saw tooth may be removable from its associated holder and typically includes at least several separate cutting edges thereon. Thus, when one cutting edge wears or becomes damaged and thus unsuitable for cutting, i.e. optimum cutting, the tooth in question can be removed from the holder and replaced back in place thereon with a different cutting edge in position for contacting the workpiece. Once all the cutting edges on any saw tooth have been used, the tooth can be removed from the holder and either replaced with a new tooth or repaired and/or sharpened and replaced back in position.
Some such removable saw teeth and their associated holders are described in the following U.S. patents, the entire contents of which are incorporated herein by reference: U.S. Pat. No. 5,205,199 issued on Apr. 27, 1993, U.S. Pat. No. 5,303,752 issued on Apr. 19, 1994, U.S. Pat. No. 5,307,719 issued on May 3, 1994 and U.S. Pat. No. 5,664,965 issued on Jul. 8, 1997, all to Charles D. MacLennan. Typically, such saw teeth include up to four cutting edges on a front face of the tooth, and have a flat rear face, opposite said front face, which abuts with a corresponding surface on the holder against which the tooth is fastened in engagement.
However, while such removable saw teeth for circular saws permit improved tooth life span in comparison with fixed (i.e. non-removable or non-rotatable) teeth, improvement is nonetheless desired.